* {
    margin: 0;
    padding: 0;
}

body {
    background-image: url(../img/regist.jpg);
    background-repeat: no-repeat;
    background-size: cover;
}

header {
    width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.page-header {
    width: 500px;
    margin: 0 auto;
    text-align: center;
    color: white;
}

article {
    width: 1200px;
    margin: 0 auto;
    background-color: white;
    border-radius: 15px;
}

article>div {
    width: 400px;
    height: 400px;
    margin: 0 auto;
    padding-top: 20px;
}

nav {
    margin-top: 20px;
    display: flex;
    justify-content: center;
}

nav li {
    width: 200px;
    text-align: center;
}

.table th,
.table td {
    text-align: center;
}